This invention relates to a wheelchair that provides the user with the ability to exercise therapeutically his or her legs and hips while sitting in place or propelling the chair. More specifically, the present invention involves a wheelchair attachment that offers the capability of exercising the lower body to a large number of disabled or handicapped individuals.
Often time when people are unable to walk due to post-operative recoveries, injuries or the like, their unused muscles become weakened and the body loses strength. Typically, when a recovery is lengthy or not possible, the individuals must attend therapy on a regular basis. This type of therapy is not only time consuming, but expensive in that the patient usually must be transported from a place of confinement to the therapist's office. This, in turn, can result in missed appointments due to bad weather, help shortages, lack of transportation and the like. Under these types of adverse conditions, a patient can soon lose a desire to continue in therapy.
A manually propelled wheelchair is disclosed in U.S. Pat. No. 4,993,732 wherein a patient seated in the chair can manually drive the wheels through means of a pair of hand-operated levers. The levers are hand pumped back and forth and the motion translated to the main drive wheels of the chair through a suitable linkage to cause the wheels to rotate in a forward direction. Although this device exercises the patient's upper body, it does not therapeutically aid the lower part of the body which, in many cases, is the part of the body that most needs exercise.
U.S. Pat. No. 5,273,304 discloses a leg powered attachment for a conventional wheelchair. A single drive wheel unit equipped with pedals is simply connected to the wheelchair frame by a pipe. The person seated in the chair then pedals the drive wheel much like a child's tricycle. The pedals are directly coupled to the drive wheels and, as anyone who has ridden a tricycle knows, pedaling can tire the operator rapidly. In the case of a disabled or handicapped person, pedaling the wheelchair using this type of system could be overtaxing and self-defeating. A similar drive system is disclosed in a later U.S. Pat. No, 5,280,937 where the direct pedal drive is replaced by a combination sprocket and chain drive unit which offers some improvement. This device, however, requires the chair casters to be removed and replaced by the auxiliary drive unit, thus preventing the chair from being used in a conventional manner.
A wheelchair is disclosed in U.S. Pat. No. 5,324,060 which is again quite similar to that described in the above noted '937 patent. Here again, a frame is attached to a wheelchair and contains a drive wheel coupled to a pair of foot peddles by a conventional bicycle sprocket and chain arrangement. Like many of the similar prior art devices, this combination wheelchair and bicycle can overtax a disabled person and negates the ability to use the chair in a conventional manner.